The renoprotective effects of taurine against diabetic nephropathy via the p38 MAPK and TGF-ß/Smad2/3 signaling pathways.

Diabetic nephropathy (DN), a severe diabetes complication, causes kidney morphological and structural changes due to extracellular matrix accumulation. This accumulation is caused mainly by oxidative stress. Semi-essential amino acid derivative taurine has powerful antioxidant and antifibrotic effects. The aim of this study was to investigate the renoprotective effects of taurine through its possible roles in oxidative stress, extracellular matrix proteins, and the signaling pathways associated with the accumulation of extracellular matrix proteins in DN rats. 29 Wistar albino rats were randomly separated into control, taurine, diabetes, and diabetes + taurine groups. Diabetes animals were injected 45 mg/kg streptozosine. Taurine is given by adding to drinking water as 1% (w/v). Urine, serum, and kidney tissue were collected from rats for biochemical and histological analysis after 12 weeks. According to the studies, taurine significantly reduces the levels of malondialdehyde (MDA), total oxidant status (TOS), and protein expression of NADPH oxidase 4 (NOX4) that increase in diabetic kidney tissue. Also, decreased superoxide dismutase (SOD) activity levels significantly increased with taurine in diabetic rats. Moreover, increased mRNA and protein levels of fibronectin decreased with taurine. The matrix metalloproteinase (MMP)-2 and MMP-9 activities and their mRNA levels increased significantly, and this increase was significantly summed with taurine. There was a decrease in mRNA expression of Extracellular matrix metalloproteinase inducer (EMMPRIN). Taurine significantly increased this decrease. Diabetes increased mRNA expressions of transforming growth factor (TGF)-ß and Smad2/3. Taurine significantly reduced this induction. TGF-ß protein expression, p38, and Smad2/3 activations were also inhibited, but taurine was suppressed significantly. All these findings indicate that taurine may be an effective practical strategy to prevent renal diabetic injury.

Role of p38 MAPK, Akt and NFκB in renoprotective effects of nebivolol on renal ischemia-reperfusion injury in rats.

Renal ischemia-reperfusion (I-R) injury is a complex pathophysiologic condition characterized by oxidative stress, inflammation and apoptosis. We investigated the potential renoprotective effect of nebivolol, a ß1 adrenergic receptor blocker, against renal I-R injury. We focused on the role of nebivolol in activating p38 mitogen-activated protein kinase (MAPK) signaling, Akt (protein kinase B) and nuclear factor-κB (NFκB) transcription factors, which contribute to oxidative stress, inflammation and apoptosis during renal I-R. We divided 20 adult male Wistar albino rats into three experimental groups. Group 1 was a sham control in which only laparotomy was performed. Group 2 was the I-R group in which both kidneys were made ischemic for 45 min, then reperfused for 24 h. Group 3 was the I-R + nebivolol group in which 10 mg/kg nebivolol was administrated by gavage for 7 days before I-R. We measured Inflammation, oxidative stress and active caspase-3 as well as activation of p38 MAPK, Akt (protein kinase B) and NFκB transcription factor. Nebivolol significantly reduced oxidative stress and increased superoxide dismutase levels during renal I-R. We found that nebivolol significantly decreased interstitial inflammation, and TNF-α and interleukin-1ß mRNA expression. Nebivolol significantly reduced active caspase-3 and kidney injury molecule-1 (KIM-1) expressions. Nebivolol also significantly decreased activation of p38 MAPK signaling and NFκB, and induced Akt activation during renal I-R. Our findings suggest that nebivolol may be useful for management of renal I-R injury.

The Effect of Laughter Yoga on the Psychological Resilience and Sleep Quality of Nurses During the Pandemic: A Randomized Controlled Trial.

Background: During the COVID-19 pandemic, nurses frequently experienced psychological health problems such as anxiety, depression, insomnia, and stress. These problems have reduced the psychological health of nurses. Primary Objective: This study aims to reveal the effect of laughter yoga on the psychological resilience and sleep quality of nurses during the COVID-19 pandemic. Design: This randomized controlled trial study was carried out using an experimental research design with pre- and post-tests, including a control group. Setting: This study was conducted on nurses working in a hospital in Erzurum, located in the northeastern part of Turkey. Participants: The study involved 90 nurses, including 46 in the experimental group and 44 in the control group, between October and December 2021. Intervention: As an intervention, laughter yoga sessions were held online on Zoom for nurses in the experimental group. The experimental group was divided into three groups of 17, 17, and 16 individuals. Eight sessions of laughter yoga (two days a week for four weeks) were offered to nurses in the experimental group. Primary Outcome Measures: The Introductory Question Form, Connor-Davidson Resilience Scale, and Pittsburgh Sleep Quality Index were used for data collection. Results: Laughter yoga significantly improved the resilience levels and sleep quality of the experimental group (P < .05). Conclusion: Laughter yoga can be used to improve the resilience and sleep quality of nurses.

The relationship between nurses' work stress levels and work-family conflict during the COVID-19 pandemic and the affecting factors: A study from Turkey.

PURPOSE: High work-family conflict affects nurses' physical, mental and psychological health and reduces their job satisfaction and performance. This study was conducted to determine the effect of work stress experienced by nurses during the COVID-19 pandemic on family life and the factors affecting work stress and work-family conflict. METHOD: This descriptive and cross-sectional study was conducted on 820 nurses who agreed to participate in the research working in a hospital serving only patients with confirmed COVID-19 in a province in eastern Turkey. RESULTS: It was found that the average PJSS score of the nurses included in the study was 3.26 ± 0.56; the average WAFCS score was 3.00 ± 0.81. It was found that there was a moderately positive, statistically significant relationship between the PJSS and WAFCS average scores for the nurses, and the impact of work stress on the levels of work-family conflict was 28 % (p < 0.001). CONCLUSION: It was determined that the work stress levels of the nurses included in the study were at a level that could threaten their health, the conflict levels in work-family life were high, and the conflict levels in work and family life increased as the levels of work stress increased.

Evaluation of the Neuroprotective Effect of Pycnogenol in a Hypoxic-Ischemic Brain Injury Model in Newborn Rats.

OBJECTIVE: This study aimed to evaluate the efficacy of Pycnogenol (PYC) and its antioxidant and antiapoptotic effect in an experimental hypoxic-ischemic (HI) rat model. STUDY DESIGN: A total of 24 Wistar albino rats who were on the seventh postnatal day were divided into three groups with developed HI brain injury model under the sevoflurane anesthesia: 40 mg/kg PYC was given to Group A, saline was given to Group B, and the sham group was Group C. Neuronal apoptosis was investigated by terminal deoxynucleotidyl transferase dUTP nick end labeling and immunohistochemically stained manually with primer antibodies of tumor necrosis factor-α and interleukin-1ß. RESULTS: The neuronal cell injury was statistically lower in the PYC treatment group. CONCLUSION: This is the first study that investigates the role of PYC in the HI brain injury model. PYC reduces apoptosis and neuronal injury in the cerebral tissue of the rats. PYC may be a protective agent against hypoxic-ischemic encephalopathy. KEY POINTS: · This is the first study that investigates the role of PYC in the HI brain injury model.. · PYC may be a protective agent against hypoxic-ischemic encephalopathy.. · Sevoflurane should not be preferred in rat studies where neuronal apoptosis will be investigated..

The effect of yoga on pain level in primary dysmenorrhea.

This study was conducted to evaluate the effect of yoga on pain levels in female students with primary dysmenorrhea. This study is a randomized experimental study with control group and pretest post-test practice. This study included 60 volunteer female students (30 experimental and 30 control groups). The patients in the experimental group took part in the yoga program a total of 12 sessions, once per week for 12 weeks. "Personal Information Form", "Visual Analog Skala (VAS)" and "Dysmenorrhea Monitoring Form (DMF)" were used in data collection process. To measure dysmenorrhea pain, the students were requested to mark a number between 1 and 10 on the VAS scale according to the severity of their pain on the menstruation starting date. The yoga applications were used for three menstrual cycles. The mean age of the students in the experimental group was 20.30 ± 0.46, while the mean age of the students in the control group was 20.46 ± 0.50. The difference between the pain levels of the students in the experimental group in the first, second, third and fourth measurements was found to be statistically significant (p < 0.001). It was determined that the difference between the pain levels of the students in the control group in the first, second, third and fourth measurements was not statistically significant (p > 0.05). Yoga can be used as an effective intervention in reducing menstrual pain in women with primary dysmenorrhea.

Prevention of microbial colonization of feeding tubes in the intensive care unit.

BACKGROUND: Various microorganisms which increase the mortality rate in the intensive care unit (ICU) cause microbial colonization of the nasogastric tube (NGT) and use the NGT as a reservoir. AIM: To detect the colonization on the NGT and to determine the effect that training regarding hand hygiene, NGT management, and enteral feeding (EF) provided to ICU nurses and auxiliary service staff (ASS) has on the level of NGT colonization. STUDY DESIGN: A quasi-experimental pre-test and post-test control design was used in this study. Microbial samples were taken from the outer and inner parts of NGT. The microorganisms were categorized as: group 1, no risk; group 2, low risk pathogenic; group 3, high-risk pathogenic group. The training was given to nurses (n = 15) and ASS (n = 7). Hand hygiene, NGT, and EF care training are provided to nurses and ASS by researchers. A total of three training sessions were scheduled to be held in 3 weeks so that all health care staff members were trained. Each session lasted 2 h in total. Patients were assigned to a group if one of the microorganisms presented on the outer surface of the patient's feeding tube and/or on the hub. The hand hygiene compliance was evaluated by direct observation according to the World Health Organization hand hygiene indications. RESULTS: The study was conducted with 46 patients. Evaluating the patients for the presence of microorganisms before education revealed that 4.3% were in group 1, 21.8% were in group 2, and 73.9% were in group 3. After the education, evaluating the samples for the presence of microorganisms revealed that 39.1% were in group 1, 13% were in group 2, and 47.8% were in group 3. A statistically significant difference was found between the number of samples included in the groups after the participants had received training (H = 8.186; p = .017). CONCLUSIONS: An NGT could act as a reservoir of microbial colonization and high-risk microorganisms could be on the tube. Providing training not only to nurses but also to ASS will help reduce the risk of colonization. RELEVANCE TO CLINICAL PRACTICE: Eliminating such colonization with effective hand hygiene during NGT feeding is a cost-effective method. Providing training not only to nurses but also to ASS will help obtain the optimum benefit from patient care.

Evaluation of syringin's neuroprotective effect in a model of neonatal hypoxic-ischemic brain injury.

Background/aim: A significant cause of mortality and morbidity in the neonatal era is hypoxic-ischemic encephalopathy (HIE). This study examined the histopathological analysis and neuroprotective impact of syringin (SYR) in an experimental HIE rat model. Material and methods: On the 7th postnatal day, 24 Wistar albino rats were evaluated in 3 groups using the HIE model under gas anesthesia. In the experiment, Group A received 10 mg/kg SYR plus dimethyl sulfoxide (DMSO), Group B received DMSO only, and Group C served as a sham group. Immunohistochemical techniques were used to assess apoptotic cell measurement and proinflammatory cytokines (TNF-α and IL-1ß primary antibodies). Results: Rats suffering from hypoxic-ischemic brain damage had their apoptosis assessed. The SYR and sham groups had statistically fewer cells undergoing apoptosis (p < 0.001). There was no difference between the groups in terms of IL-1ß and TNF-α during immunohistochemical staining. Neuronal degeneration was significantly lower in the histological evaluation of the hippocampus in the SYR group (p = 0.01). A statistically significant difference (p = 0.01) was observed between the SYR and the control groups regarding pericellular and perivascular edema. Conclusion: SYR reduced apoptosis, perivascular and pericellular edema, and neuronal degeneration in rat cerebral tissue. These results raise the possibility that SYR may have a neuroprotective effect on the harm brought on by HIE. This is the first investigation of SYR's function within the HIE paradigm.

The Profile of Caring: An Internationally Tested Model to Assess and Support Nurses During Pandemic.

The psychological impact of the COVID-19 pandemic on nurses, and subsequent increases in turnover, have been extensively documented. This article examines a profile of nurses which included (1) the degree to which direct-care nurses are caring for themselves, (2) the degree to which their manager acts in a caring way, (3) the degree to which nurses have clarity about their professional role and about how the system works, and (4) the degree to which nurses are satisfied with essential social and technical dimensions of their jobs, to help understand how some of the critical internal states and working relationships of nurses fit together as a model. To test the model, authors used structural equation modeling with a 35-item measurement tool in three countries (Russia, Serbia, and Turkey; n = 984), replicating a recent 8-country study. Results revealed a good model fit, similar to the original study, despite statistically significant differences in mean scores between the countries studied. Good model fit with a second group of countries, despite differences in mean scores, suggests that results from both studies can be used for a global conversation about how caring, clarity, and job satisfaction in nursing relate to one another. These results provide evidence that health facilities should study variables such as caring for self, caring by the unit or department manager, clarity of role and system, and job satisfaction to learn about, recover, and monitor nurses' health and experience of work as they emerge from the pandemic.

Validity and Reliability of the Turkish Version of the Breast Cancer Screening Beliefs Scale.

OBJECTIVE: Breast cancer is an important public health problem because of its frequent occurence and fatal consequences. Early diagnosis of breast cancer increases the treatment success and survival. For the early diagnosis of breast cancer, women's screening beliefs and attitudes need to be determined. This study aimed to examine the reliability and validity of the Breast Cancer Screening Beliefs Scale to determine patients' beliefs and attitudes regarding breast cancer screening. MATERIALS AND METHODS: This methodological study was carried out with 261 women. A survey form and the Turkish version of the Breast Cancer Screening Beliefs Scale were used in the data collection. Coverage validity was determined by the coverage validity index, and the Davis technique, item-total score correlations, Cronbach alpha evaluation, factor analysis, and AMOS analysis were used. RESULTS: The factor structure of the 13-item Turkish version of the Breast Cancer Screening Beliefs Scale was examined. After the factor analysis, a threefactor structure emerged which accounted for 70% of the total variance and has an eigenvalue of over 1.00. In the internal consistency analyses of the scale, item-total score correlation values ranged from 0.37 to 0.90, and no items were extracted from the scale. CONCLUSION: The Turkish version of the Breast Cancer Screening Beliefs Scale was found to be a valid and reliable measurement tool in determining the screening beliefs and attitudes of women.

Comparison of the Fear Levels and Sleep Problems of Nurses Working in Wards Where Patients with and without COVID-19 Are Hospitalized: A Study from Turkey.

BACKGROUND: This study was carried out to compare the fear levels and sleep problems of nurses working in wards where patients with COVID-19 are hospitalized and nurses working in wards without COVID-19 patients. SUBJECTS AND METHODS: This descriptive, cross-sectional research was conducted on 211 nurses using a web-based online survey in Turkey (including 104 nurses working in wards where patients with COVID-19/107 nurses working in wards where patients without COVID-19). RESULTS: When the COVID-19 Fear Scale mean scores of the nurses working in wards where patients with/without COVID-19 were compared, it was determined that the difference between the groups was statistically significant (p<0.05). When the sleep problems experienced were compared according to the Post-Sleep Inventory, it was determined that the difference between the groups was not statistically significant (p>0.05). There was a moderately significant and positive correlation between the nurses' mean scores for the COVID-19 Fear Scale and Post-Sleep Inventory. CONCLUSIONS: It was determined that as the fear levels of nurses increased, they experienced more sleep problems.

Effect of progressive relaxation exercises on primary dysmenorrhea in Turkish students: A randomized prospective controlled trial.

BACKGROUND: A randomized prospective controlled study was conducted concerning the effects of progressive relaxation exercises on the reduction of pain in primary dysmenorrhea. MATERIALS AND METHODS: The research control group (CG) consisted of 60 students while the experimental group (EG) consisted of 64 students. The progressive relaxation exercises were self-administered via compact disc (CD) by participants for two menstrual cycles. A descriptive information form, a visual analog scale (VAS) and a dysmenorrhea monitoring form (DMF) were used for data collection. RESULTS: The difference between the average first and final post-exercise measurements of the VAS scores of students in the experimental group was statistically significant (p < 0.001), whereas the difference in the control group was not statistically significant (p > 0.05). CONCLUSION: Progressive relaxation exercises are an effective method for reducing dysmenorrhea when they are performed on a regular basis.

Relationship between the social support and psychological resilience levels perceived by nurses during the COVID-19 pandemic: A study from Turkey.

PURPOSE: The aim of this study was to determine the relationship between the social support and psychological resilience levels perceived by nurses in Turkey during the coronavirus disease-2019 (COVID-19) pandemic. DESIGN AND METHODS: The study was descriptive and cross-sectional. FINDINGS: The level of social support perceived by the nurses during the COVID-19 pandemic was very good, and the perceived psychological resilience level was moderately good. Moreover, their psychological resilience was found to increase as the social support perceived by them increased. PRACTICE IMPLICATIONS: Psychiatric nurses should determine the social support resources of nurses, especially during the epidemic period. Individual and institutional studies should be conducted to increase nurses' psychological resilience.

Turkish version of the childbirth perception scale: Reliability and validity study.

PURPOSE: This study aimed to adapt the Childbirth Perception Scale (CPS) to the Turkish language and to test its validity and reliability. DESIGN AND METHODS: This methodological study was conducted with 240 puerperants. FINDINGS: The confirmatory factor analysis of the index values showed a good fit. The internal consistency coefficients were 0.74 for the delivery perception, 0.65 for the first postpartum week perception and 0.70 for the total. The total correlation of the CPS items and the test-retest correlation showed high-reliability levels. PRACTICE IMPLICATIONS: Based on the study results, the Turkish language version of the CPS is valid and reliable.

The effect of a course on violence against women on the attitudes of student midwives and nurses towards domestic violence against women, their occupational roles in addressing violence, and their abilities to recognize the signs of violence.

AIM: The aim of this study was to determine the effect of a course on violence against women on the attitudes of student midwives and nurses towards violence against women and their abilities to recognize the signs of violence. METHODS: This study used a pretest-posttest quasi-experimental design with experimental and control groups and was conducted with student midwives and nurses. RESULTS: The results indicated that the difference between pretest and posttest scores averaged across three scales was statistically significant for students in the experimental group (P < 0.001) and not statistically significant for students in the control group ( P > 0.05). PRACTICE IMPLICATIONS: The traditional attitudes of students who enrolled in the course on violence against women decreased, and their levels of knowledge of signs of violence increased.

Prevalence and risk factors for domestic violence against infertile women in a Turkish setting.

OBJECTIVE: Our objective was to estimate the prevalence and risk factors for domestic violence among women seeking infertility treatment at an IVF center. STUDY DESIGN: This cross-sectional study was conducted with 423 infertile women who referred to the IVF Center in the southwest of Turkey between 1 January and 31 July 2016. The women were interviewed without their male partners by using the questionnaire and Infertile Women's Exposure to Violence Determination Scale. RESULTS: A total of 306 participants (72%) declared having experienced domestic violence. It was found that 30% of the women exposed to violence stated that they were subject to physical violence, 6% to sexual violence, 62% to emotional violence, and 19% to economic violence. It was determined that the total mean score obtained by the women exposed to violence from Infertile Women's Exposure to Violence Determination Scale was 120.04 ± 12.69 and when it was evaluated based on the total mean scores to be obtained from the scale, level of violence experienced by the women was found to be severe. CONCLUSIONS: The rate of exposure to violence was determined to be high in women included in the study. The most common type of domestic violence is psychological violence.

The validity and reliability of the Antenatal Perceived Stress Inventory Turkish version: A methodological study.

The aim of the authors in this study was to adapt the Antenatal Perceived Stress Inventory developed abroad into Turkish for the evaluation of perceived stress during pregnancy. This study consisted of 350 primigravidas who attended the outpatient clinic of Nenehatun Women's Birth Hospital in Erzurum city in eastern Turkey between 10 March 2015 and 4 January 2016. The Prenatal Distress Scale and Turkish version of the Antenatal Perceived Stress Inventory were used to collect data through face-to-face interviews. The data were analyzed using SPSS for Windows and LISREL software packages. Explanatory and confirmatory factor analyses, Cronbach's alpha coefficients, split-half testing, parallel forms reliability, and test-retest methods were used to determine the validity and reliability of the Antenatal Perceived Stress Inventory. The average age of the participants was 23.51 ± 3.82. The total score average for perceived stress on Turkish version of the Antenatal Perceived Stress Inventory was 2.28 ± 0.90. The Cronbach's alpha coefficient of the Antenatal Perceived Stress Inventory was 0.70, the item-total point correlations were between 0.36 and 0.56, and the correlation value of the test-retest was 0.98. In the parallel forms reliability conducted to determine the equivalence of the scales, there was a statistically significant correlation between Turkish version of the Antenatal Perceived Stress Inventory and The Prenatal Distress Scale (r = 0.689, p < 0.001). The results of the explanatory factor analysis revealed that a three-factor structure, with factor loadings in the range of 0.36-0.79 explained 43.56% of the total variance. The results of the confirmatory factor analysis confirmed the validity of the three-factor structure of the scale and that the data fit of the model was acceptable. It was established that the Turkish version of Antenatal Perceived Stress Inventory was a valid and reliable measurement instrument. This scale can be used for the evaluation of perceived stress in Turkish pregnant women.

Pretreatment with paricalcitol attenuates level and expression of matrix metalloproteinases in a rat model of renal ischemia-reperfusion injury
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BACKGROUND: Ischemia-reperfusion injury (IRI) is a leading cause of acute kidney injury (AKI). The inflammatory response that drives IRI involves upregulation of matrix metalloproteinases (MMPs), which results in proteolytic degradation of renal microvascular matrix. Evidence suggests a potential protective role of active vitamin D on ischemic injury by downregulating MMPs. In the present study, we aimed to determine the expression and level of MMP-2 and MMP-9 in renal IRI model and the potential beneficial effect of paricalcitol on both level and expression of MMPs and tubular injury caused by IRI. MATERIALS AND METHODS: 20 Wistar albino rats were divided into three groups: sham-operated, ischemia-reperfusion, and paricalcitol-pretreated. IRI model was induced by bilateral clamping of renal arteries for 45 minutes followed by 24 hours of reperfusion. The analysis of serum creatinine and levels of MMPs were performed after 24 hours of IRI. The effects of paricalcitol on the quantity and expression of MMP-2 and MMP-9 in renal tubular epithelial cells were investigated by enzyme-linked immunosorbent assay and immunohistochemistry, respectively. The pathological examinations were performed to score tubular damage by light microscopy. RESULTS: Creatinine levels decreased in the paricalcitol group, although this was not proven to be significant. Rats in the paricalcitol group showed significant decrease in both level and expression of MMPs and in tubular injury scores as compared to the IRI group. CONCLUSION: Paricalcitol may attenuate renal tubular injury caused by IRI by decreasing both level and expression of MMPs. Further studies are required to investigate the interplay between activated vitamin D and MMPs in AKI.
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Pretreatment with nebivolol attenuates level and expression of matrix metalloproteinases in a rat model of renal ischaemia-reperfusion injury.

AIM: Matrix metalloproteinases (MMPs) are zinc-containing proteinases that are involved in the degradation of extracellular matrix (ECM) and a number of cell surface proteins in order to maintain tissue homeostasis. They are involved in pathogenesis of several ischaemic organ injuries. In the present study, we aimed to determine the expression and level of MMP-2 and MMP-9 in renal ischaemia-reperfusion injury (IRI) model and the potential beneficial effect of nebivolol, a ß1 -adrenergic receptor blocker, on both MMP-2 and -9 level and expression and tubular injury caused by IRI. METHODS: Twenty Wistar albino rats were divided into three groups: sham-operated , ischaemia-reperfusion, and nebivolol-pretreated. IRI model was induced by bilateral clamping of renal arteries for 45 min followed by 24 h of reperfusion. The analysis of serum creatinine levels, quantity and expression of MMP-2 and MMP-9 were performed after 24 h of IRI. The effects of nebivolol on level and expression of MMP-2 and MMP-9 levels were investigated by enzyme-linked immunosorbent assay and immunohistochemistry, respectively. The pathological examinations were performed to score tubular damage by light microscopy. RESULTS: Creatinine levels increased significantly in the ischaemia-reperfusion group compared to the sham-operated group. Rats in the nebivolol-pretreated group showed significant decrease in expression and quantity of MMP-2 and MMP-9 during IRI. The pathological examinations demonstrated significantly low level of tubular injury score in nebivolol-pretreated group. CONCLUSION: Nebivolol attenuated IRI by decreasing the expression and level of MMP-2 and MMP-9.

Effect of nitrergic system on colonic motility in a rat model of irritable bowel syndrome.

AIM: The aim of this study is to investigate whether nitric oxide (NO)-mediated colonic motility was altered in rat irritable bowel syndrome (IBS) model, using different isoforms of NO-synthase (NOS) inhibitors. MATERIALS AND METHODS: The animal model of IBS-like visceral hypersensitivity was induced by intra-colonic infusion of 0.5% acetic acid (AA) in saline once daily from postnatal days 8 to 21. Control animals received saline instead of AA. Experiments were performed at the end of 8 weeks. Distal colon tissues were resected and direct effects of different NOS inhibitors; N-omega-nitro-L-arginine methyl ester hydrochloride, (L-NAME), ARL-17477 dihydrochloride hydrate (ARL 17477), N-[3-(Aminomethyl) phenyl] methyl]-ethanimidamidedihydrochloride (1400 W), and N5-(1-Iminoethyl)-L-ornithine dihydrochloride (L-NIO) were evaluated concentration-dependently in vitro tissue bath. Besides, morphology of both groups was assessed with hematoxylin and eosin (H and E) staining and the impact of NO antibodies was determined using the immunohistochemical method. RESULTS: The mean pressure values of spontaneous contractions and KCL (80 mmol/L) responses of distal colonic segments were similar in normal and IBS rats. L-NAME and ARL-17477 significantly increased the mean pressure of spontaneous colonic contractions in normal rats versus own base values (P < 0.05), but this increase did not significantly different when compared to IBS rats. In H and E staining, there was no difference with regard to morphology between two groups. Neuronal NOS (nNOS) immunoreactivity was found to be significantly decreased in IBS when compared to control groups (P < 0.05). CONCLUSION: L-NAME and ARL-17477 mediated mean pressure values were found to be slightly decreased in IBS rats. These findings may be related to a decrease in nNOS level in IBS.